Electric switch



June 9, 1942. P. M. FARMER l ELECTRIC swITcH Filgduaroh 24, 1958 l l l ll l l l fill/ll., lill FIG.|

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INVENTOR P. M. FARMER BY i a: 1l y...

ATTORN EY Patented June 9, 1942 ELECTRIC SWITCH Paul M. Farmer,Maplewood, N. J., assignor to American District Telegraph Company, NewYork. N. Y., a corporation of New Jersey Application March 24, 1938,Serial No. 197,783

9 Claims.

This invention relates to manually operated switches for initiatingholdup alarm signals of the type which can be silently operated by asubstantially invisible movement of the holdup Victim and can be easilyconcealed in a desk or the like. It also relates to a switch having anindicating means therein for indicating operation of the switch so thatif a person inadventently sends a holdup signal he cannot later allegethat a fault in the alarm system itself has caused a false alarm.Therefore, a switch is provided which will be locked in the operatedposition and which has an indicator that is also locked in position toindicate switch operation.

In the event of a holdup it is desirable to initiate an alarm signalthereby bringing aid to the victim and catching the holdup man. However,this must be done without the knowledge of the bandit since it ispossible that he will harm the victim and also be able to escape if herealizes that an alarm signal has been initiated. Therefore the victimmust be able to initiate an alarm by means of an invisible switch whilehe is making some perfectly normal motion and the switch must benoiseless in operation so that the bandit will not be alarmed by anyclicks or the like. It is also desirable to have some means ofidentifying the switch which initiates the holdup alarm since itfrequently occurs that in stores, banks, offices or the like a clerkwill become unduly alarmed by some suspicious movement of an innocentperson and send in a holdup alarm thereby bringing guards or police orboth. When they arrive, to absolve himself, the clerk will frequentlyallege that the alarm system was at fault and initiated a false alarm,but when the holdup alarm switches are locked in operated position andhave indicators. to show which switch has been operated, it quicklybecomes evident to the guards or police whether or not the alarm systemwas at fault.

Therefore, it is an object of this invention to provide a switch whichcan be easily concealed and which is noiseless in operation.

Another object of this invention is to provide a switch which can beoperated during a normal motion executed by the holdup victim during aholdup.

A further object of this invention is to provide an improved indicatingdevice which will indicate an operated condition of a holdup alarmswitch.

Another object of this invention is to provide a holdup alarm switchwhich will not be operated readily by accidental pressure thereon oi'any other accidental contact therewith.

Another object of this invention is to provide a switch having anindicator therein which will be locked in its operated position toindicate that it has been operated and which can only be restored tonormal position by a person having the proper key.

A further object of this invention is to provide a holdup alarm switchwhich can be silently operated by a slight motion of one finger andwhich can be easily concealed about a desk, counter or the like.

Another object of this invention is to provide a holdup alarm switchwhich, after being operated to initiate a holdup alarm, will be lockedin such a position that its operation will be indicated and which canrepeatedly be operated to initiate a holdup alarm without first beingunlocked and restored to its normal position.

Other objects of the invention will appear from the followingdescription of the preferred embodiments thereof shown in theaccompanying drawing wherein:

Fig. 1 shows a plan view of the holdup alarm switch.

Fig. 2 shows a plan view partly in section of the alarm switch in itsnormal position.

Fig. 3 shows the alarm switch in its operated position and the key forrestoring the switch.

Fig. 4 shows a section of Fig. 3 on the line 4 4.

Fig. 5 shows an end View partly in section.

Fig. 6 shows a modication of the alarm switch in diagrammatic form.

Fig. 7 shows the same modication in the operated position.

Fig. 8 shows the same modification in an intermediate position.

The holdup alarm switch is shown in the drawing in substantially itsactual size. By referring to Figs. 1 and 4 it is evident that the switchis small and inconspicuous and therefore can be easily mounted in aconcealed position such as on a desk or other piece of furniture. InFig. l, numeral I indicates the cover of the switch, while 2 indicates afingerhole therein. In Fig. 2 the numeral 5 indicates a finger operatedblock for the purpose of controlling the springs II, I2, I3, I4, I8 andI9 which are operated as shown in the drawing by the cam surfaces 8 and9, linger block 5 being slidable between the lugs 6 at the side of theblock. It should be noted here that the finger block 5 is completelyenclosed within the cover I thereby preventing any accidental operationof the switch by pressure thereon or any other inadvertent contact withthe switch. The operator of the switch must intentionally insert hisfinger in the linger block before operation is possible and thereforefalse alarms du'e to accidental operation are prevented. The springpile-up is conveniently fastened together byscrew members and the wholeassembly inserted in the slots I of the lug I6. The purpose ofassembling the spring pile-up in this fashion is to enable its mountingand removal on the base 4 without disassembling the whole spring pile-upas this is found to be very convenient both in manufacture and for thepurpose of repair. In order to insure silent operation of the switch,the felt or other'v resilient members and 2| are inserted between theiinger block 5 and the end projection I0 mounted on the base 4, and thelocking springs I8 and I9 are silenced by the felt member 22. Thus whenthe nger block is pulled to the operated position therehwill be noclicks or other tell-tale sounds.

The hold-up alarm switch is. adapted to be easily operated withoutattracting attention; for instance in the case ofa person sitting behinda desk, he will ordinarily rise to a standing position if threatened bya hold-up man and will usually grasp the desk in his hand. Whilegrasping the desk in this manner it is very easy to hook'ones finger inthe finger hole 3l of the iinger block 5 where the switch is mountedunderneath the desk to operate the switch inconspicuously and silentlywhile he is rising to a standing position. In this particularapplication of the switch, the hold-up victim will have initiated aburglar alarm without any warning whatever to the hold-upV man.Operation of the finger block 5 closes the spring contacts II and I2 toground the alarm circuit and opens the spring contacts I3 and I4 tobreak the alarm circuit as shown in Fig. 6. Therefore the switch isadapted for insertion in the usual types of burglar alarm systemswherein ground and break operation are used. Operation of the switchallows the springs I8 and I9 to approach each other, thereby preventingresetting of the switch as shown in Fig. 3. This particular feature isvery desirable since it often happens that clerks in banks or storeswill send in false alarms due to suspicious actions of innocent persons.When guards or police respond to these alarms the person responsiblewill often reset the ordinary hold-up alarm switch and blame the alarmsystem for the false alarm in order to vindicate himself, whereas thepresent invention avoids any misapprehension as to the operation of thealarm system by providing the indicator 23 and the locking mechanismmentioned above which prevents the switch being reset, The guards orpolice responding to an alarm will iind Van operated switch and beingequipped with a key such as the key I6 shown in Fig. 3, will insert itthrough hole I'I of the finger block 5 to spread springs I8 and I9thereby resetting the switch to its normal position.

A further modification of the switch is shown in Figs. 6, 7 and 8. Insome instances it is desirable that even though the switch has beenv Inthis construction, the i will open and the spring members I3 and I4 willclose after operation of the finger block. Contact members 25 and 26,shown in Fig. 6, are provided for operating an annunciator to indicatean alarm. Referring to Fig. 7, it should be noted that when the fingerblock is in its operated position there is a spacing between the element9 of the nger block 5 and springs I9, whereas in the construction shownin Fig. 3 there is no such spacing. rihus the springs 28 and 29 willreturn the finger block to the position shown in Fig. 8, therebyrestoring the contacts Il, I2, I3 and I4 to their normal position.However, the indicator 23 is still in p-osition to show that the switchhas been operated and the switch is in an intermediate position where itcan still be operated to initiate a burglar alarm.

Fig. 5 shows a detail of the construction of the finger block 5 and thebase member 4. In its usual installation the switch is mounted with thecover downward. Thus when the cover is re- -ioved for the purpose ofrepair or inspection, it

is desirable that the nger block 5 will not drop out of the switch. Theextension l of the base member 4 is provided with a shoulder 3|), whilethe nger block is also provided with a cooperating shoulder 3I. Theseshoulders are approximately one thousandth of an inch wide and cooperateto retain the finger in its proper position, but they will allow thefinger block to be sprung out of place so that it may be removed with nodifficulty. l

Various other modifications may be made in the construction andarrangement of parts without departing from the spirit of the inventionset forth in the appended claims.

I claim:

1. In combination, a pair of normally closed Contact springs, a pair ofnormally open contact springs, a pair of locking springs, a base forsupporting said contacts and springs, a nger pull block mounted on saidbase, recessed portions in said block for engaging said locking springs,two other recessed portions in said block which engage said contactsprings, a keyhole in said block. a key member engaging said lockingsprings and a tell-tale mounted at one end of said block.

2. In combination, a base member, a lug integral with said base member,slots in said lug, a contact spring pileup, screw members in said pileupand engaging said slots, a linger pull block engaging said springpileup, a finger hole in said block, a keyhole in said block, earmembers on said base member adapted to engage said block, a coveradapted to cover said spring pileup and said block, a nger hole in saidcover offset slightly with respect to the finger hole in said block,resilient members between said block and said cover, a tell-taleattached to said block and projecting through said cover and a keyholein said cover alined with the keyhole in said block.

3. In combination, a base member, a spring pileup mounted thereon, amovable finger block slid-ably mounted on said base in operativerelation With said pileup, a cover on said base for concealing andenclosing said block and having an opening therein, the axis of which isnormal to the plane of motion of said block whereby said finger blockcan be manually operated.

4. In combination, a base member, a spring pileup mounted thereon, anger block mounted on said base in operative relation with said pileup,a cover on said base for concealing and for protecting said block havingan opening therein whereby said finger block can be operated and anindicator mounted on said ilnger block and projecting through saidcover.

5. In a switch, a base member, a spring pileup thereon, an operatingmember for operating said pileup, a cover on said base, said pileup andsaid member being mounted within and concealed by said cover, said coverhaving a finger hole therein at one side of said operating member forallowing opera-tion of said member transversely of said fingerhole.

6. In a switch, a finger block, a spring pileup adapted to be operatedthereby and comprising at least one set of contacts and a set of lockingsprings for locking said finger block in operated position, means forenclosing and concealing the entire mechanism, an aperture therein forproviding access to the block, an indicator for indieating the operatedcondition of said block and means for maintaining said block in such aposition that the indicator shows an operated condition and in such aposition that the block can still operate the contacts.

7. In combination, a unitary spring pileup comprising at least one setof contact springs and a set of locking springs, a finger pull blockhaving operating surfaces for engaging and operating said contactsprings and other surfaces engaged by the locking springs, a keyhole insaid block and a key member for engaging said locking springs forreleasing said block.

8. In combination, a unitary spring pileup comprising contact springsand locking springs, a movable nger block having portions in a planewith said pileup for engaging and operating said contact springs andother portions for engaging said locking springs whereby said lockingsprings prevent restoration of said block to its normal position, acover for concealing the pileup and block and an indicator attached tothe block and movable through the cover whereby operation is indicated.

9. In a switch, a base member, a unitary spring pileup mounted thereon,said pileup comprising contact springs and locking springs, a movablefinger block for operating the contact springs and so associated withsaid pileup that said block may be locked by the locking springs when itis operated, a keyhole in said finger block and in operative relation tothe locking springs and a key member for engaging and releasing saidlocking springs to unlock the block.

-PAUL M. FARMER.

